Merocyanine and holopolar dyes containing arylene-chain substitution



July 13 1965 L. G. s. BRooKER ETAL. 3,194,805

MEROCYANINE AND HOLOPOLAR DYES CONTAINING' ARYLENE-CHAIN SUBSTITUTION Filed sept. 2. 1960 Fig.1

Jlll MTN! INTI-ITW! Illl IH! IIII 50o 40o soo eoo voo my. 1-DICYANOMETHYLENE-2-(1-METHYL-20H) NAPHTHo- [1,2] THIAZOLYLIDENQJNDAN 30o 40o soo eoo y mom/.L 2- DlcYANoMETHYLENE-1,3Dl(3 -METHYL- 2 (a H) BENzoTHlAzoLYL/DENE) :NDAN

Eig

TH/AZOLYLIDENE) ETHYLIDENE] -3- [(3 -ETHYL-z (3 H) B ENz'oxAzoD/LIDENE) ETHYUDEN E] INDAN Leslie G.S. B ro ulcer Frank (i. Webster IN V EN TORS .ATIORNE Y S United States Patent O MERCYANINE AND HOLUPLAR DYES CN- Y This invention relates to holopolar cyanine dyes, a method for preparing such dyes and photographic silver halide emulsions spectrally sensitized with such dyes.

It is, therefore, an object of our invention to provide new holopolar cyanine dyes. vide new holopolar cyanine dyes having different absorbing characteristics from other holopolar cyanine dyes previously described in the photographic art. Still another object is to provide photographic silver halide emulsions spectrally sensitized with the new holopolar cyanine dyes of our invention. Other objects will become apparent from a consideration of the following description and examples.

The new spectral sensitizing dyes of our invention include holopolar cyanine dyes represented by the following two general formulas:

(CH2) D-I R/ \o=N wherein R and R1 each represents a substituted or unsubstituted alkyl group (e.g., methyl, ethyl, n-propyl, nbutyl, isobutyl, n-amyl, isoamyl, -methoxyethyl, -ethoxyethyl, allyl (i.e., vinylmethyl), benzyl (pheny1methyl), -phenylethyl, carboxymethyl, l-carboxyethyl, -sulfoethyl, 'y-sulfopropyl, y-sulfobutyl, -sulfobutyl, etc.) (especially alkyl groups containing from 1 to 4 carbon atoms), R2 represents a cyano group or an alkoxycarbonyl group (methoxycarbonyl, ethoxycarbonyl, etc., especially a lower alkoxycarbonyl group), n, m and p each represents a positive integer of from 1 to 2, d and q each represents a positive integer of from 1 to 3, D represents the atoms necessary to complete a benzene ring (which can be substituted, for example, by chlorine, bromine, hydroxyl, methoxyl, ethoxyl, methyl, ethyl, etc.), Q represents the non-metallic atoms necessary to complete a nucleus of the indandione series (e.g., 1,3-diketohydrindene, etc.) or a heterocyclic nucleus containing from to 6 atoms in the heterocyclic ring, such as those of the pyraz'- olone series (e.g., 3-methyl-l-phenyl-S-pyrazolone, 1- phenyl-S-pyrazolone, 1-(2-benzothiazolyl)-3-methyl-5-pyrazolone, etc.), those of the isoxazolone series (e.g., 3- phenyl-5(4H)isoxazolone, 3-methyl-5(4H) isoxazolone, those of the yoxindole series (e.g., 1-alkyl2,3dihydro2 oxindoles, etc.), those of the 2,4,6-triketohexahydropy- Another object is topro- ICC rimidine or 2-thio-4,6-diketohexahydropyrimidine series (eg, barbituric acid or Z-thobarbituric acid) as well as their 1-alky1 (e.g., l-methyl, l-ethyl, 1npropyl, l-nheptyl, etc.), or 1,3-dialkyl (e.g., 1,3-dimet-hyl, 1,3-diethyl, 1,3-di-n-propyl, 1,3-diisopropy1, 1,3-dicyclohexyl, 1,3-di- (-methoxyethyl), etc.), or 1,3-diaryl (e.g., 1,3-diphenyl, 1,3-di (p-chlorophenyl) 1,3-di (p-ethoxycarbonylphenyl) etc.), or 1-aryl (e.g., 1pheny1, 1-p-chlorophenyl, l-p-ethoxycarbonylphenyl, etc.), or 1-alkyl-3-aryl (e.g., 1ethyl 3-phenyl, 1-n-heptyl-3-phenyl, etc.) derivatives, those of the rhodanine series (i.e., 2-thio-2,4thiazolidinedioue series), such as rhodanine, 3-a1kylrhodanines (e.g., 3-ethylrhodanine, 3-allylrhodanine, etc.) or 3-arylrhodanines (e.g., B-phenylrhodanine, etc.), etc., those of the 2(3H) imidazo[1,2a]pyridone series, those of the 5,7dioxo-6',7 dihydro-S-thiazolo[3,2-a1pyrimidine series (e.g., 5, 7di oXo-3-pheny1-6,7dihydro 5 thiazolo[3,2-a]pyrimidine, etc.), those of the Z-thio-Z,4-oxazolidinedione series (i.e., those of the 2-thio2,4(3H, 5H)oxazoledione series (e.g., 3-ethyl-Z-thio2,4oxazolidinedione,, etc.), those 0f the thianaphthenone series (e.g., 3(2H)thianaphthenone, etc.), those of the 2-thio-2,S-thiazolidinedione series (i.e., the 2-thio2,5(3H, 4H)thiazoledione series) (e.g., 3-ethyl-2-thio-2,S-thiazolidinedione, etc.), those of the 2,4- thiazolidinedione series (e.g., 2,4-thiazolidinedione, 3-ethyl-2,4thiazolidinedione, 3-phenyl-2,4-thiazolidinedione, 3- a-naphthyl-2,4-thiazolidinedione, etc.), those of the thiazolidnone series (e.g., 4-thiazolidinone, 3-ethy1-4-thiazolidinone, 3-phenyl-4-thiazolidinone, 3-a-naphthyl-4fthiaz'olidinone, etc.), those of the 4-thiazolinone series (e.g., 2- ethylmercapto-4-thiazolinone, 2-alkylphenylamino-4-thiazolinones, 2-diphenylamino-4-thiazolinone, etc.), those of the 2-imino-2,4oxazolinone (i.e., pseudohydantoin) series, those of the 2-4-imidazolinedione (hydantoin) series (e.g., 2,4-imidazolinedione, 3ethyl-2,li-imidazolinedione, 3-phenyl-2,4imidazolinedione, 3-r1aphthyl2,4im idazolinedione, 1,3diethy1-2,4imidazolinedione, l-ethyl- 3-ocnaphthyl2,4-imidazolinedione, 1,3-diphenyl 2,4 -imidazolinedione, etc.), those of the 2thio2,4imidazoline dione (i.e., 2-thiohydantoin) series (e.g., 2-thio2,4im idazolinedione, S-ethyl-Z-thio 2,4 imidazolinedione, 3- phenyl2tl1io2,4-irnidazolinedione, 3-a-naphthyl-2-thio2, 4-imidazolinedione, l,3-diethyl2thio2,4 imidazolinedione, 1-ethyl-3-phenyl-Z-thio-2,4imidazolinedioue, 1-ethyl-3a-naphthyl-Z-thio-2,4-imidazolinedione, 1,3-diphenyl- 2-thio-2,4-imidazolinedione, etc.), those of the S-imidazolinone series (e.g., 2-n-propylmercapto-S-imidazolinone, etc.), etc. (especially a heterocyclic nucleus containing 5 atoms in the heterocyclic ring, 3 of said atoms being car- III.

s bon atoms, 1 of said atoms being a nitrogen atom, and 1 of said atoms being selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom), and Z and Z1 each represents the non-metallic atoms necessary to complete =a heterocyclic nucleus containing from to 6 atoms in the heterocyclic ring, such as those selected from the group consisting of those of the thiazole series (eg,

thiazole, 4-methylthiazole, 4-phenylthiazole, 5rnethylthi` azole, 5,-phenylthiazole, 4,5-dirnethylthiazole, 4,5-diphenylthiazole, 4(2thienyl)thiazole, etc.), those of the -benzothiazole series (e.g., benzothiazole, 4-chlo'robenzothiazole, S-chlorobenzothiazole, -chlorobenzothiapzole, 7- chlorobenzothiazole, 4methylbenzothiazole, 5 -methylbenzothiazole, -methylbenzothiazole, 5-brornobenzothiazole, -6bromrobenzothiazole, 4-phenylbenzothiazole, 5f phenylbenzothiazole, 4-methoxybenzothiazole, 5-rnethoXy- ,benzothiazole, -niethoxybenzothiazole, 5-iodobenzothiazole, -iodobenzothiazole, 4-ethoxybenzothiazole, 5-ethoxybenzothiazole, tetrahydrobenzothiazole, oxybenzothiazole, 5,6-dioxymethylenebenzothiazole, 5-hydroxybenzothiazole, -hydroxybenzothiazole, etc.), those 5,6-dirnetl1- f CFI zole, S-methylbenzoxazole, S-phenylbenzoxazole, 6-methylbenzoxazole, 5,6 dimethylbenzoxazole, 4,6 dimethylbenzoXazole, S-methoxybenzoxazole, 5-ethoxybenzoxazole, S-chlorobenzoxazole, -methoxybenzoxazole, 5-hydroxybenzoxazole, -hydroxybenzoxazole, etc.), those of the naphthoxazole seriesV (eg, naphtho[l,2]oxazole, naphtho[2,1]oxazole,l etc.), those ofthe selenazole series (e.g., 4-methylselenazole, 4-phenylselenazole, etc.), those of the benzoselenazole series (e.g., benzoselenazole, 5-

'chlorobenzoselenazolm S-methoxybenzoselenazole, S-hydroxybenzoselenazole, tetrahydrobenzoselenazole, etc. those of the naphthoselenazole series (e.g.', naphtho [1,2]se1enazole, naphtho[2,1]selenazole, etc.), those of the thiazoline series (e.g., thiazoline, 4-methylthiazoline,

etc.), those of the 2-quinoline series (e.g., quinoline, 3-

methylquinoline, Sfmethylquinoline, 7-methylquinoline, 8-methylquinoline, 6-chloroquinoline, 8-chloroquinoline, 6-methoxyquinoline, 6-ethoxyquinoline, -hydroxyquinoline, 8`hydroxyqunoline,{etc.),'those of the 4quinoline series (e.g., quinoline, -methoxyquinoline, 7rnethylquin oline, S-methylquinoline, etc.), those of the l-isoquinoline series (e.g., isoquinoline, 3,4-dihydroisoquinoline, etc.),` those of the 3isoquinoline series (e.g., isoquinoline, etc.), those ofthe benzimidazole series (e.g., 1,3-diethylbenzimidazole, 1,3-diethyl-S-chlorobenzimidazole, 1,3-diethyl-5, 6-dichlorobenzimidazole, l-ethyl-3 phenylbenzimidazole, etc.), those of the 3,3-dialkylindolenine series (c g., 3,3- dimethylindolenine, 3,3,Satrimethylindolenine 3,3,7trimethylindolenine, etc.), those of the 2-pyridine series (eg, pyridine, S-methylpyridine, etc.), those of ther4`- pyridine series (eg, pyridine, etc.), etc.

We .have also found that photographic silver halideV emulsions *can* be usefully sensitized by incorporating therein at least one merocyanine dye selected from those represented by the following two general formulas:

@leases wherein R, R2, n, d, VQ and Z each have the values given above, and D1 represents the iatoms necessary to coinplete an vindanV or l,2,3,4ftetnahydronaphth-alene ring (which can have substituents on the benzene ring thereof, `such as those identified above under D) .7 Y

Thelmerocyanine dyes represented .by Formula III above can advantageously be prepared by Acondensing a compound selected from those represented by the following gen'eral formula: Y

wherein D1- and AQ each have the values given above, with lone molecule of cycllarnmonium'quaternary salttselee-ted from those represented bythe following general formula:

VL Z

@cri-ori) 1=1-r X Y wherein R, Z ,and n each have the'values given above, X represents an acid anion, such as chloride, bromide, iodide, perchlorate, thiocyanate, benzenesulfonate, p-toluenesulfonate, methylsulfate, ethylsulfate, etc., and I represents an ,electrone'gative group, such as selected from those represented by the following general yformula:

VII.

with one Vmolecule of `a cyclamrnoniumquaternary salt selected .from those represented by -Formulta VI above.

The holoprolar koyan'ine dyes represented by Formula nIrabovre yman-be prepared by condensing a merocyanine dye selectedfrom thoserepresentedbyFormula Ill with a cyolarnrnonium quatern'ary salt represented by Formula VI. This method of preparation is capable of yieldfing symmetrical (Z and Z1 are identical) or unsym- Ymetrical (Z and Zllare diierent) dyesfy l The holopolar cyanine dyes of Formula II `can be pre- -pared by condensing a merocyanine dye of Formula TV .with a cyclammoniurn quaternary salt selected from those Yrepresented by FormulaVI. `Likewise, Athis method. of preparation is capable of yielding both symmetrical yand unsymmetroal dyes.

Symmetrical holopolar cyanine dyes included within the scope of Formula I can likewise be prepared by condensing one molecule of a compound of Formula V with two molecules lof a cyclammonium quaternary salt represented by Formula VI. In like manner, symmetrical holopolar cyanine dyes of the type included within Formula II can be prepared by condensing one molecule of an intermediate `of the type represented by Formula VII with two molecules of a cyclamrnonium quaternary salt of the type represented by Formula VI.

'Ilhe condensations of the compounds of Formula V with those of Formula VI and the condensations of the compounds of Formula VII with those of Formula VI can be accelerated by basic condensing agents, Isuch as trialkylamines (e.g., triethylamine, tri-n-propylamine, triisopropyllamine, tri-n-butylamine, etc), N,N-dialkyl anilines (e.g., N,Ndimethylianiline, N,Ndiethylaniline, etc..), N alkylpiperidines (e.g., N methylpiperidine, N-'ethylpiperidine, etc), etc. The condensation-s can also zbe carried `out in the presence of an inert diluent (depending somewhat on the solubility of the intermediates in the diluent), such as the lower `alcohols (e.g., ethanol, n-propanol, isopropanol, n-butanol, etc.), pyridine, quinoline, isoquinoline, 1,4-dioxane, etc. Basic di-luents, such as, pyridine, quinoline, isoquinoline, etc., Iare yespecially useful. Heat `accelerates the condensations, although it has been found that temperatures varying from ambient (ca. l25" C.) to the reux temperature of the reaction mixture can -be employed.

The intermediates of Formula V above can advantageously be prepared by condensing a compound selected from those represented by the following general formula:

VIII.

wherein D1 has the Values given above, wit-h an intermediate of t-he following general formula:

wherein R2 has the values given above.

The condensations of the compounds of Formula VIIIv with those of Formula IX or X can advantageously be carried out in the presence of a mixture of ammonium acetate and acetic acid. Generally, an inert diluent, such as chloroform, diethyl ether, etc. can be employed. Heat accelerates the condensations although temperatures varying from room temperature to about the relluxing temperature of the reaction mixture can be employed.

In preparing the merocyanine dyes of Formula III and those of Formula IV, it is apparent that the intermediates of Formulas V and VII need have only one reactive methylene group, as indicated in the formulas. However, in preparing the holopolar dyes of Formula I and Formula II, it is apparent that the intermediates of Formula V and Formula VII must have two reactive methylene groups. Intermediates of Formula V having two reactive methylene groups can be represented by the following general formula:

wherein D, Q and p each have the values given above. The intermediates fo Formula VII having two reactive methylene groups can be represented by the following general formula:

H2O CH2 XII.

wherein R2, D and p each have the values given above.

'Ihe following examples will serve to illustrate the preparation of the intermediates and sensitizing dyes of our invention, as well as the sensitizing action of these dyes when incorporated in yordinary photographic silver halide emulsions.

Example 1.--1-dicyanomethylenendzm A mixture of 39.6 g. (1 mol.) of l-indanone, 19.8 g. (1 mol.) of malononitrile, 2.5 g. of ammonium acetate, 4 ml. of acetic acid and 40 ml. of chloroform was heated at the reuxing temperature until approximately 5.4 ml. of water was collected in a Dean and Stark distillation receiver. The chloroform solution was concentrated to dryness and the solid was recrystallized from methanol. The yield of grayish-white crystals was 65% and they had a M.P. or 147148 C.

yield of tan crystals was 73% and they had a M.P. of -193 C.

A mixture of 19.0 g. (1 mol.) of 2-indanone, 26.5 g. (1 mol.) of 1,3-diethylbarbituric acid, 2.5 m1. or" piperidine and 100 ml. of ethanol Was heated at the reuxing temperature fortwo hours. The reaction mixture was chilled, the solid was collected on a filter and Washed with methanol. After one recrystallization from ethanol, the yield of colorless needles-Was 47% and theyhad Ya M.P. of 165-167/ C.

Example 4 .--1 -dcyanlomethylened ,2,3 ,4-itetrahydranaphthalene vAmixmm of 36.4 g. (1 m01.) of r-tetraione, 13.2 g'. (1 mol.) of malononitrile, 2.5 g. of ammonium acetate,

V4 m1. of acetic acid and 100 m1. of chloroform was heated at rthe reuxing temperature for 16 hours.

The water was collected in a Dean and Stark distillation receiver. The reaction mixture Was concentrated to dryness and the residue stirred in water. The water was decanted and the residue was stirred in ethanol. The solid ,Was collected on a filter and Washed with ethanol. The yield of colorless crystals was 48% and they had a M.P. of 107- 108" C.

Exampl e 5 .-Z-dzcyanomethylenee] ,2,3 ,4-tetrahydronaphthalene g CN Example 6.-] -dicyanomethylene-Z- (3-m ethyl-2 (3H) benzothiazolyld'ene) ndan Us\cw% f .N/ y,

climv /C\GN Y A mixture of 5.4 g. (1 mol. plus 50% excess) of 1di cyanomethyleneindan,` 7.4 g. (1 mol.) of 3-methyl-2- methylrnercaptobenzothiazolium p-toluenesulfonate, 6.06

g. (1 mol. plus 200% excess) of triethylamine and 50 ml. Y

The reaction mixture was tit of ethanol was `heated at the reiluxing temperature forlS minutes. The reaction mixture was chilled and the solid was collected on a lter and washed with methanol. The solid Was stirred inhot methanol, Vthe suspension was ltered ;hot, .and .the solid was washed With methanol. The dye Was dissolved in hot pyridine, the solution was iltered,'methanol was added, and afterv chilling `the dye was collectedon a filter and the dye was washed lwith methanol. After anothersuch purification, the yield of dye Was 35%. The felt of orange crystals had a M.P. of 24S-246 C. with decomposition, and they sensitized a photographic gelatinosilverbromoiodide emulsion t'o about 565 lma with maximum sensitivity at about 545 ma.

S VV Y Hz ll (112m C Y No/ \oN' A mixture of 5.4 g. (1- mol.) of l-dicyanomethyleneindan, 13.5 g. (l mol.) of 2-(2facetanilidovinyl)-3ethy1 benzothiazolium iodide, 6.0 g. (1 mol. plus V100% excess) of triethylamine and 50 ml. of` ethanol Was hearted at the reiluxing temperature for 30 minutes.V v`Thev reaction .mixture Waschilled, `the solid was collected Ona lter and Washed with methanol. The dye was dissolved in hot pyridine,` the solution Was filtered, methanol was added, and after chilling the dye was collected on a lter and Washed with methanol. After another such. purification, the dye was recrystallized from pyridine. The shiny green needles had a MP. of 259--260c C. with decomposition and Vthey sensitized a photographic gelatine-silver-bromoiodide emulsion Vto about 680 ma witha maximum sensitivity at about l660 ma. 1

Example 8.-] -dz'cyanom-ethylene-Z- (3-ehyl42(-3H benzothazolylidene)-2-batenyldene1iadan zHs A mixture or 0.9 g.-(1 mol.) of l-dicyanomethyleneindan, 2.38 g. (1 mol.) of'2-(4-acetanilido-1,3-butadif enyl)-3-ethylbenzothiazolium iodide, 1.0 g. (1 mol. plus excess) of triethylarnine and 15 ml. of ethanol was heated at the refluxing temperature for 15 minutes. The reaction mixture Was chilled, the solid Was -collected on a ilter and washed with methanol. The dye Wasfdissolved in hot pyridine, the solution was iiltered, methanol Was added,.and yafter .chillingthe Vdye was collected on a filter and washedwith'methanol. After another such purication, .the yield of dye was 36%. The shiny darli green crystals `had a M P. of 240241 C. with decomnposition.

Example 9.-]-dicyanomellzylene-Z- (3-methyl-2 (3H)-V A mixture of 3.32 g. (2 mol.) of Z-methylmercaptobenzoxazole and 3.72 g. (2 mol.) of methyl p-toluenesulfonate was heated to the boiling point over a free flame. The reaction mixture was chilled and washed with two successive portions of ether. To the sticky residue, 1.8 g. (1 mol.) 'of l-dicyanomethyleneindan, 2.0 g. (2 mol.) of triethylamine and 15 ml. of ethanol were added. The reaction mixture was heated at the reiiuxing temperature for l minutes. After chilling, the solid was collected on a iilter and washed with methanol. After two recrystallizations from ethanol, the yield of dye was 28%. The dark reddish-brown crystals had a M.P. of 230-231 C. with decomposition, and they sensitized a photographic gelatino-silver-bromoiodide emulsion to about 510 mp. with maximum sensitivity at about 490 me.

rr a N/ A mixture of 0.7 g. (1 m01.) of 1-dicyanomethyleneindan, 3.57 g. (1 mol. plus 100% excess) of l-methyl-Z- methylmercaptonaphtho[1,2]thiazolium methylsulfate, 1.0 g. (1 mol. plus 100% excess) of triethylamine and 15 ml. of ethanol was heated at the reiiuxing temperature for minutes. The reaction mixture was chilled, the solid was collected on a iilter and washed with methanol. The dye was dissolved in hot pyridine, the solution was filtered, and after chilling the dye was collected on a ilter` and washed with methanol. After another such purification, the yield of dye Was 55%. The red crystals with a gold reflex had a M.P. of 265-267 C. With decomposition, and they sensitized a photographic gelatino-silver-bromoiodide emulsion to about 575 mp with maximum sensitivity at about 550 mp. Y

A mixture of 0.9 g. (1 mol.) of l-dicyanomethyleneindan, 2.19 g. (1 mol. plus 100% excess) of 1-ethyl-2- phenylmercaptoquinolinium p-tolucnesulfonate, 1.0 g. (l mol. plus 100% excess) of triethylamine and 15 ml. of ethanol was heated at the reliuxing temperature for 10 minutes. The reaction mixture was stirred in water, the water was decanted, the residue was stirred in two successive portions of ether, the residue was stirred yin methanol, the solid was collected on a filter and Washed With methanol. The dye was dissolved in hot pyridine, the solution was filtered and after chilling, the dye was collected on a iilter and Washed with methanol. After another such puriiication, the yield of dye Was 19%. The dark coppery crystals had a M.P. of 227228 C. with decomposition.

10 Example 12.-] -dicyanomethylene-Z- (l-ethyl-2 (1H) naphtho [1,2] thz'azolylidene) sopropyldelne] ndane A mixture of 0.9 (1 mol.) of 1dicanomethyleneindan, 2.19 g. (1 mol.) of 1-ethyl-2-(2-ethylrnercaptopropeny1) naphtho[1,2]thiazolium ethylsultate, 1.0 g. (1 mol. plus excess) of triethylamine and 15 m1. of ethanol was heated at the reiiuxing temperature for 15 minutes. The reaction mixture was chilled, the solid was collected on a iilter and Washed With methanol. The dye was dissolved in hot pyridine, the solution was filtered, methanol was added, and after chilling the dye was collected on a lter and washed with methanol. The yield of dye Was 1%. The darky crystals with coppery reflex had a M.P. of 191- 193 C. with decomposition, and they sensitized a photographic gelatino-silver-bromoiodide emulsion.

Example I 3 .-Zdicyanomethylene-I (3 -ethyl-Z (3H benzothazolylz'dene indan A mixture of 2.0 g. (l mol.) of 2-dicyanomethyleneindan, 3.49 g. (1 mol. plus 10% excess) of 3-ethyl-2- ethylmercaptobenzothiazolium ethylsulfate, 1.1 g. (1 mol. plus 10% excess) of triethylamine and 25 ml. of ethanol was heated at the reiiuxing temperature for 15 minutes. The reaction mixture was chilled, the solid Was collected on a lilter and Washed with methanol. Ihe dye was dissolved in hot pyridine, the solution Was ltered, methanol was added and after chilling the dye was collected on a -ilter and washed with methanol. After another such purification, the yield of dye was 46%. The dark green crystals with a green reflex had a M.P. of 256-258 C. with decomposition.

Example 14 In a like manner, 2- dicyanomethylene-1[(3-ethyl-2 (3H)-benzothiazolylidene)ethylidene]indan was prepared from 5.4 g. (1 mol.) 4of 2-dicyanomethyleneindan, 13.5 g. (1 mol.) of 2-(2-acetanilidovinyl)-3-ethylbenzothiazolium iodide, 3.3 g. (1 mol. plus 10% excess) of triethylamine and 50 ml. of ethanol. The yield of dye, after one more recrystallization from pyridine was 21%. The green crystals with a coppery reflex had a M.P. of 246- 250 C. with decomposition.

Example 15 In a like manner, 2-dicyanomethylene-1-[(3-ethyl-2 (3H) -benzothiazolylidene)-Z-butenylidenejindan was prepared from 5.4 g. (1 mol. of 2-dicyanomethyleneindan, 9.52 g. (1 mol.) of 2-(4-acetanilido-1,3-butadienyl)-3- ethylbenzothiazolium iodide, 3.3 g. (1 mol. plus 10% excess) of triethylamine and 75 m1. of ethanol. The yield of dark green crystals was 22% and they had a M.P. of 28-230 C.

Example 16 In a like manner, 2dicyanomethylene-1[(3-ethyl-2 (3H)-benzoxazolylidene)ethylidene]indan was prepared from 5.4 g. (1 mol.) of 2-dicyanomethyleneindan, 12.72 g. (1 mol.) of 2-(2-acetanilidovinyl)-3-ethylbenzoxazoliurn iodide, 3.3 g. (1 mol. plus 10% excess) of triethylamine and 75 ml. of ethanol. The yield of shiny green crystals was 28% and they melted at 214215 C, with decomposition.

I 9 I CH3 NC/ CN CH3 A mixture of 1.8 g. (1 m01.) of 2-dicyanometl'1y1ene-` methylcercaptobenzothiazolium p-toluenesulfonate, 2.2 g.

(2 mol. plus 10% excess) of triethylamine and 25 m1. of

Cil

ethanol was heated at the refluxing temperature for l minutes. The reaction mixture was chilled, the solid was A mixture of 1.98 g. (1 mol.) of 2-dicyanomethylene- 1[(3ethyl 2(31-1) benzothiazolylidene)ethylidene]in dan, 2.25 g. (l mol.) of 2-(2acetanilidovinyl)3-etl1yl benzothiazoliumiodide, 0.6 g. 1 mol. plus 10% excess) of triethylamine Vand l5 ml. ofpyridine was heated at the refluxing temperature for minutes. The reaction mixture was chilled, the solid was collected on `a lilter and Washed with methanol. The dye Was extracted with two 350 ml. portions of hot pyridine. The yield of vdye after extractions was 33%. The dark green crystals had a MP. of 288-289 C. and they sensitized a photographic gelatino-silverebromoiodide emulsion to aboutr 780 mp. with maximum sensitivity at about690 mp.

12 y Example l19.--2dicyanorrzethylene] (3-ethyl2 (3H benzothz'azolylidene -2-butenyldene] (S-thyl- 2 (3H) benz0thiaz0lylidene)ethylidene] indan was dissolved in hot pyridine,fthe solution was filtered, methanol was added, and after chilling the solid was collected on a filter and-washed with methanol. After another such purification,-the yield of dye was 35%. The black crystals hada Ml. of 244-245 C. with decomposition, kand they sensitized a photographic gelatinesilver-bromoiodide emulsion to about 840 mp with maximum sensitivity at about 810 mp.

Example 20,-2-.dcyanomethylene-I- (A3-thyl-2 (3H) benzothazolylidene)ethyldene] -3- (3-ethyl-2 (3H) benzoxazolyldene)ethylidene] indan VA mixture of 1.9 g. (1 mol.) of2-dicyauomethylene-1- [(3 f ethyl '2(3H) benzoxazolylidene)ethylidene]indan, 2.25 g. (l mol.) ofy 2-(2facetanilidovinyl)-3-ethylbenzothiazolium iodine, 0.6`g. (1 mol. plus'l0% excess) of triethylamine and 15 ml. of pyridine was heated at the refluxing temperature for 15 minutes. yThereactionv mixture was stirred in Water. The solid was collected on a filter and Washed with methanol. The dye was 'dissolved in hot pyridine, the solution was filtered, methanol Was added, and after chilling the dye was collected on a lter and Washed Example 18.-Z-dcyanomethylene-1,3-di (3-ethyl- 2 (3H )benz0thazolyldene) -Z-butenylidene] indan 02H5 A mixture of 2.14 g; (1 mol.) of Z-dicyanomethyleneportions of hot methanol, the solid was collected on ay lter and Washed with hot methanol. The dye was dissolved in hot pyridine, the solution was filtered, methanol was added, and after chilling the dye Was collected on a filter and washed with methanol. After another such purification, the yield of dye was 13%. The dark crystals had 4a MP. of 2317-238" C. with decomposition and they sensitized a photographic gelatino-silver-chlorobromide emulsion to about 690 mp with maximum sensitivity at about 630 mp.'

with methanol. Afterk another such purification, the yield of dye was 45%. The silver-gray needles had a M.P. of Z-256 C. with decomposition, and they sensitized a photographic gelatine-silver-bromoiodideV emulsion Vto about 730 mp with maximum sensitivity at about 685 mp.

Example 21 .-1,3-dethyl-5 [1- (3-methyl'2 (3H) -benzothazolylzdene)hindan-2-ylidene] barbiturc acid edeeeee A mixture of 6.56 g. (1 mol. plus 10% excess) of 1,3-

'The solid was extracted in a soxhlet With ether to remove 1,3-diethyl-5-(indan-2-ylidene)barbituric acid. The yield of dye after two recrystallizations from pyridine was 12% The reddish-brown crystals had a M.P. of 272-273 C. with decomposition.

A mixture of 5.96 g. (1 mol) of 1,3-diethyl-5-(indan-2- ylidene)barbituric acid, 14.28 g. (2 mol.) of S-methyl-Z- methylmercaptobenzothiazolium p-tolueriesulfonate, 4.0 g. (2 mol.) of triethylamine, and 25 ml. of ethanol was heated at the reiluxing temperature for 15 minutes. The reaction mixture was chilled, the solid was collected on a filter and the solid was extracted with ether. The dye was dissolved in hot pyridine, the solution was filtered, water was added, and after chilling the dye was collected on a filter and Washed With Water. After a recrystallization from ethanol, the yield of dye was 28%. The red crystals with a green reex had a M.P. 310 C.

A mixture of 1,3-diethy1-5-(indan-Z-ylidene)barbituric acid, 4.5 g. (2 mol.) of 2-(2-acetanilidovinyl)-3-ethylbenzothiazolinm iodide, 4.0 g. (2 mol. plus 100% excess) of triethylamine and 30 ml. of ethanol was heated at the reuxing temperature for 110 minutes. The solid was collected on a filter from the hot reaction mixture and the solid was washed with methanol. The dye was dissolved in hot cresol, the solution was ltered, methanol was added, and after chilling the dye was collected on a lter and Washed with copious quantities of methanol. After another such purification, the yield of dye was 61%. The olive-green crystals had a M.P. 310 C. and they sensitized a photographic gelatino-silver-bromoiodide emulsion to about 770 my. With maximum sensitivity at about 750 mit.

l 02C 02H5 A mixture of 1.49 g. (1 mol.) of 1,3-diethyl-5-(inda11- f 2ylidene)barbituric acid, 4.34 g. (2 mol.) of 2-(2-acetanilidovinyl)-3-ethylbenzoxazolium iodide, 2.0 g. (2 mol. plus excess) of triethylamine and 25 ml. of ethanol was heated at the refluxing temperature for 10 minutes. The reaction mixture was chilled, the solid was collected on a lter and Washed with methanol. The dye was dissolved in hot cresol, the solution was ltered, methanol was added, and after chilling the dye was collected on a lter and washed with copious quantities of methanol. After another such purification, the yield of dye was 41%. The shiny green crystals had a M.P. of 280-281" C. with decomposition, and they sensitized a photographic gelatinosilver-bromoiodide emulsion to about 720 mp With maximum sensitivity at about 680 ma.

S\\G= C/S\ 'M El C2H5-N N-C2H5 C l A mixture of 1.46 g. (l mol.) of 1,3-diethyl-5-(indan- 2-ylidene)barbituric acid, 4.6 g. (2 mol. plus 10% excess) of 1-methyl-Z-methylmercaptonaphtho[1,2]thiazolium ptoluenesulfonate, 1.1 g. (2 mol. plus 10% excess) of triethylamne and 15 ml. of pyridine was heated at the reluxing temperature for lO'minutes. The reaction mixture was stirred in Water, the residue was dissolved in pyridine and Water Was added. The solid was collected on a :filter and washed with water. The dye was dissolved in hot pyridine, the solution was ltered, Water was added, and after chilling the solid was collected on a lter and Washed with Water. After another such purication, substituting ethanol for pyridine, the yield of dye was 62%.

The dark crystals had a M.P. of 242-243 C. With dccomposition, and they sensitized a photographic gelatinosilver-bromoiodide emulsion to about 620 mp. with maximum sensitivity at about 590 ma.

V.ilter'and washed with Water.

l A mixture of 1.11 g. (1 mol.) of 1,3-diethyl-5-[l-(3- barbituric acid, 1.23 g. (1 mol. plus 10% excess) of 2-(4- acetanilido-1,3-butadieny1) -3-ethylbenzothiazolium iodide, 0.6 g. (l mol. plus excess) of triethylamine and 15 ml. of pyridine was heated at the reuxing temperature for 10 minutes. The reaction mixture was stirred in methanol and after chilling the solid wascollccted on a lter.

and washed with methanol. The dye was dissolved in hot cresol, the solution was filtered, methanol was added and after chilling the dye was washed with copious quantities of methanol.V After another such purification, the yield of dye was 27%. The green crystals with a coppery reex had a MP. of 285-286 C. with decomposition, and they sensitized a photographic gelatino-silver-bromoiodide vemulsion to about 810 ma with maximum sensitivity at about 73.0 m/L.

A mixture of 1.11 g. (1 mol.) of 1,3-diethyl-5-[l-(3- methyl 2(3H) benzothiazolylidene)indan 2 ylidene] barbituric acid,2.08 g. (2 mol. plus 10% excess) of 1- methyl 2 methylrnercaptonaphtho[1,2]thiazolium ptoluenesulfonate, 0.6 g. (2 mol. plus 10% excess) of triethylamine and 20 ml. of pyridine was heated at the reflnxing temperature for 10 minutes. The reaction mixture was stirred in water, the residue was dissolved in pyridine and water was added. After chilling the solid was collected on a filter and washed with water. The dye was dissolved in hot pyridine, the solution was filtered, water Was added, and after chilling the dye Was collected on a After another such purification, using ethanol for pyridine, the yieldv of dye was 54%. The dark red crystals with a green reflex had a M.P. of 231232 C. with decomposition and they sensitized a photographic gelatino-silver-bromoiodide emulsion to about 575 ma with maximum sensitivity at about 555 mp..

Example 28.-] -dicyanomethylene-I ,2,3,4-tetrahydro2- (3 -methy l-2(3H -benz0thaz0lyldene) naphthalene (|1113 No/ \CN A mixture of 0.97 g. (l mol.) of 1-dicyanomethylene- 1,2,3,4-tetrahydronaphthalene, 3.57 g. (1 mol. plus 100% excess) of 3-methyl-2-methylmercaptobenzothiazolium ptoluenesulfonate, 1.0 g. (1 mol. plus 100% excess) of tri-V Example 29 In ya like manner, l-dicyanomethylene-l,2,3,4tetrahy dro 2 (l methyl 2(1H)naphtho[1,2lthiazoly1idene) naphthalene was prepared from 0.97 g. (1 mol.) of l-dicyanomethy1ene-l,2,3,4-tetrahydronaphthalene, 4-.12 g. (1

.mol. plus 100% excess) :of 1-rnethyl-Z-methylmercaptonaphtho[1,2]thiazolium methylsulfate, 1.0 g. (1 mol. plus `100% excess) of triethylarn-ine and 15` ml. of ethanol. The yield of dye was The .red-brown crystals with a green reflex had a MiPpof 289290 C. with decom- `positon and `they sensitized a photographic gelatine-silver- Lbromoiodide emulsion lto about 580 ma with maximum sensitivity at about 555. ma.

Example. 30

In a like manner, 1- dicyanomethylene-2(1-ethyl-2 (1H) quinolylidene)-1,-2,3,4-tetrahydronaphthalene vwas prepared from 0.97 g. (1 mol.) of 1-dicyanomethylene-1, 2,3,4-tetrahydronaphthalene, 4.37 g. (1 mol. plus 100% excess) of 1-ethyl-2-phenylmercapto-quinolinium p-toluenesulf-onate, 1.0 g. (l mol. plus excess) of triethylamiue land 15 ml. of ethanol. The yield of dye was 33%. The shiny coppery-red crystals `had a M.P. of 28j-286 C. with decomposition.

n Example 31 In .a like manner, ldicyanomethylenc-2[(3-ethy1-2 (3H) benzoxazolylidene)ethylidene]-1,2,3,4tetrahydro naphthalene was prepared from 0.97 g. (l mol.) of l-d-icyanomethylene-1,2,3,4tetrahydronaphthalene, 2.4 g. (1 mol. plus 10% excess) kof 2-(2-acetanilidovinyl)-3-ethy1- .benzoxazolium iodide, 1.0 g. (l mol. plus 100% excess) of triethylarnine land 25 ml. of ethanol. The yield of dye vwas 19%. The shiny green needles had a M.P. of 213- 214" C.

with decomposition and they sensitized a photogelatino-silver-bromoiodide emulsion to about with maximum sensitivity at about 600 mp.

graphic 690 Irl/.L

Example 32 methylbenzothiazol-iumiodide, 1.0;'. (l mol.V plus 100% excess) of triethylamine .and 25 ml. of ethanol. Before the pyridine-methanol purification, the crude dye was stirred three times in hot methanol. The yield of dye was 5%.A The shiny green needles had aM.P. of 231- 232" C. with decompositon, and they ysensitized a photovgraphic gelatino-silver-bromoiodide emulsion to about 690 ma with maximum `sensitivity at .about 580 my( We have found that the intermediates of Formula V or Formula VII can be condensed with intermediates of the type represented by Formula V -in column 3 of Heseltine and Brooker U.S. Patent 2,927,026, issued March 1, 1960, to provide merocyanine dyes corresponding yto those of Formula III `and Formula IV, wherein d is 2 and wherein the methine group contiguous to the ring represented by D1 contains a substituent, such as alkyl (e.g., methyl, ethyl, propyl, etc.), or aryl (e.g., phenyl, tolyl, etc.). Where this alkyl group is methyl, it remains reactive and can be reacted with a second molecule of an intermediate of-Formula V of U.S. Patent 2,927,026 to provide complex holopolar dyes. The preparation of a merocyanine prepared using the general method `of Examplev 12. It will be noted thatY the dyes of our inventionrepresented by Formulas I and II have been named in their 17 uncharged state, although the formulas have been written in the charged form. It is possible, of course, to write the structures of these dyes in an uncharged state, for example, as follows (for Formula I):

wherein R, R1, d, m, n, p, q, D, Q, Z and Z1 each have the values given above. While the above structure represents a non-ionic representation of the dye of Formula I, it is possible to assign a related structure to the dyes of Formula II.v

As shown in the above examples, many of the dyes -of our invention are particularly useful in manufacturing photographic, lsilver halide emulsions, serving to alter the sensitivity thereof. Sensitization by means of our new dyes is, of course, directed primarily to the ordinarily employed, gelatine-silver, halide, developing-out emulsions. The dyes are advantageously incorporated in the washed, nished emulsion and should, of course, be unilformly distributed throughout the emulsion. In the preparation of photographic emulsions containing our new dyes, it is only necessary to disperse the dyes in the emulsions. Tlie methods of incorporating dyes in emulsion are simple and well known to those skilled in the art of emulsion making. 'solutions in appropriate solvents. The solvent must, of course, Ibe compatible with the emulsion and substantially free from `any deleterious effect onthe light-sensitive materials. Pyridine has proven satisfactory as a solvent for the major-ity of our new dyes.

The concentration of our new dyes in the emulsion can vary widely, i.e., from about 5 to about 100 mgs. per liter of flowable emulsion. The concentration of the dye will vary according to the type of light-sensitive material in the emulsion ,and according to the eifects desired. The suitable Iand most economical concentration for any given emulsion will be apparent to those skilled in the art upon making the ordinary tests and observations customarily used in the .art of emulsion making.

To prepare a gelat-ino-silver-halide emulsion sensitized with one of our new dyes, the following procedure is satisfactory: A quantity of the dye is dissolved in pyridine or other suitable solvent and a volume of this solution (which may be diluted with methanol) containing from 5 to 100 mgs. of dye is slowly .added to about 1000 cc. of a gelatino-silver-halide emulsion, with stirring. Stirring is continued until the dye is uniformly distributed throughout the emulsion. With most .of our new dyes, to 20 mgs. of dye per liter of emulsion suffices to produce the maximum sensitizing eifect with the ordinary gelatino-silver-bromide (including bromoiodide) emulsions. With iine-grain emulsions, which include most of the ordinarily employed gelatino-silver-chl-oride emulsions, somewhat larger concentrations of dye may be necessary to secure the optimum sensitizing effect.

The above statements are only illustrative yand are not to be understood as limiting our invention in any sense, `as it will be apparent that our new dyes can be incorporated by other methods in many of the photographic silver halide emulsions customarily employed in the art. For instance, the dyes can `be incorporated by bathing a plate or `film upon which an emulsion has been coated, in the solution of the dye, in an appropriate solvent. Bathing methods, however, are not yto be preferred ordinarily.

Photographic silver halide emulsions, such as those listed above, containing the sensitizing dyes of our inven- It is convenient to add the dyes from Y tion can also contain such addenda as chemical sensitizers, eg., sulfur sensitizers (e.g., lallyl thiocarbamide, thiourea, `allylisothiocyanate, cystine, etc.), various gold compounds (e.g., potassium chloroaurate, auric trichloride, etc.) (see U.S. Patent-S 2,540,085; 2,597,856 and 2,597,915), various palladium compounds such as palladium chloride (U.'S. 2,540,086), potassium chloropalladate (U.S. 2,598,- 079), etc., or mixtures of such sensitizers; antifoggants, such as ammonium chloroplatinate (U.S. 2,566,245), ammonium chloroplatinite (U.S. 2,566,263), benzothiazole, nitrobenzimidazole, 5-nitroindazole, `benzidine, mercaptans, etc. (see Mees-The Theory of the Photographic Process, MacMillan Pub., 1942, page 460), or mixtures thereof; hardeners, such as formaldehyde (US. 1,763,- 533), chrome alum (U.S. 1,763,533), gly-oxal (U.S. 1,870,354), dibromacrolein (British 406,750), etc.; color couplers, such as those described in U.S. Patent 2,423,730, Spence and Carroll (U.S. Patent 2,640,776), etc.; or mixtures of such addenda. Dispersing agents for -color couplers, such as those set forth in U.S. Patents 2,322,027 Iand 2,304,940, can also be employed in the above-described emulsions.

The merocyanine and holopolar dyes of our invention have unique sensitizing properties `in that maximum absorption is shifted bathochromically about millimicrons as compared with similar dyes having no ary'lenechain substitution. This unique effect is illustrated in FIGURES 1-3 of the accompanying drawing.

The accompanying drawing illustrates the `sensitizing effect obtained with three of our novel spectral sensitizing dyes in gelatino-silver-bromiodide or -chlorobromide emulsions. The solid line in each ligure of the drawing is a diagrammatic reproduction of one SpeCtrOgram. The inherent sensitivity of the emulsion is within the region of about 400 millim-icrons and th-e sensitivity contributed by the sensitizing dye is represented by the right-hand portion of the ,solid curve.

In FIGURE l, the solid curve represents the sensitivity of .an ordinary gelatino-silver-chlorobromide emulsion sensitized with ldicyanomethylene2(1-methyl-2(1H) na-phtho [1,2]thiazolylidene)indan. The preparation of this sensitizing dye is given in Example 10 above.

What we claim as our invention yand desire secured by Letters Patent of the United States is:

1. A compound selected from the group consisting of those represented by the following formula:

wherein R represents an alkyl group containing from 1 to 4 carbon atoms, R2 represents a member selected from the class consisting of the cyano group and lan alkoxycarbonyl group containing from 2 to 3 carbon atoms, a represents a positive integer of from 1 to 3, n represents a positive integer of from l to 2, D1 represents the atoms necessary to complete a ring selected from the class consisting of an indan ring and -a 1,2,3,4-tetrahydronaphthalene ring, such that the benzene ring of said indan ring and said 1,2,3,4-tetrahydronaphthalene ring is substituted alogene la naphthoxazole nucleus, a benzoselenazole nucleus, aY naphthoselenazole nucleus, a Z-quinoline nucleus, and aV 4-quinoline nucleus.

2. A compound selected from the group consisting of those represented -by the following two formulas:

wherein R and R1 Yeach represents avlowcr alkyl group, R2 represents a member selected from the class consisting of the cyauo group and a lower alkoxycarbonyl group, d and q each represents a positive integer of from l to 3, m, n and p each represents a positive integer of from l to 2, .D represents the atoms necessary to complete a ring selected from the class consisting of benzene, a halogenated benzene, a hydroxysubstituted benzene, a methoxysubstituted benzene, an ethoxysubstituted benzene,r a rnethylsubstitutedV benzene yand an ethylsubstitutedfbenzene, Q represents the non-metallic atoms necessary to complete a nucleus selected from the class consisting of an indandione nucleus, a pyrazolone nucleus, an isoxazolone nucleus, an oxindole nucleus, a 2,4,6-triketohexahydropyrimidine nucleus, a 2-thio-4,-diketohexahydropyrimidine nucleus, a rhodanine nucleus, a 2(3H)-imi dazo[l,2.a]pyridone nucleus, a 5,7-dioxo6,7dihydro5 thiazolo[3,2-a]-pyrimidine nucleus, a 2-thio-2,4oxazoli dinedione nucleus, a thian-aphtl1enone nu-cleus, a 2-rthio2,'5 thiazolidinedione nucleus, a 2,4-thiazolidinedione nucleus, a thiazolidinone nucleus, a 4thiazolinone nucleus, a 2- imino2,4oxazolinone nucleus, a 2,4-irnidazolinedione nucleus, a Z-thio2,4imidazolinedione nucleus and a 5- imdazolinone nucleus, land Z2 and Z3 each, represents the non-'metallic atoms necessary to complete a heterocyclic nucleus selected from the class Vconsisting of a thiazole nucleus, a benzothiazole nucleus, a napnthothiazole nucleus, an oxazole nucleus, a benzoxazole nucleus, a naphthoxazole nucleus, a selenazole nucleus, a 4benzoselenazole nucleus, anaphthoselenazole nucleus, a thiaz'oline nucleus, a Z-quinoline nucleus, a 4quinoline nucleus, a l-isoquinolin'e nucleus, a'BV-isoquinoline nucleus, a benzimidazole nucleus,'a 3,3-dialkylindolenine nucleus, a 2-pyridine nucleus and a 4-pyridine nucleus.

3. A compound selected from the group consisting of those represented by the formula:

wherein R` represents analkyl group -containing-rorn l to 4 carbon atoms, d Yrepresents a positive integer of from 1 to 3, h represents a positive integer of from l'tol, D1 represents the atoms necessary to complete a ring selected from the class consisting of an indan ring and -a l,2,3,4 tetrahydronaphthalene ring,such that the benzene ring of said in-dan ring and said 1,-2,3,ll-tetrahydronaphthalene ring is substituted with `aV group selected from the class consisting of the hydrogen atom, a halogen atom, the hydroxyl group, the methoxy group, the ethoxy group, the methyl group and the ethyl group, VQ represents ,the nonmetallic atoms necessary to conipletea nucleus selected from the rclass consisting of an indandione nucleus, a pyrazolone nucleus, an isoxazolonenucleus, an oxindole nucleus, a 2,4,6-triketoheXahydropyri-midine nucleus, a 2- `thio-4,6-diketohexahydropyrimidine nucleus, a rhodanine nucleus, a Z(3H)imidazo[l,2a]pyridonernucleus, a 5,7- dioxo-6,7-dihydro-5-thiazolo[3,2-a]pyrimidine nucleus, a 2-thio-2,4oxazolidinedione, nucleus, a thionaphthenone nucleus, a Z-thio-Q,S-thiazolidinedione nucleus, a 2,4-thiazolidinedione nucleus, a thiazolidinone nucleus, a 4-thiazolinone nucleus, a 2-irnino-2,4-oxazolinone nucleus, a 2,4-imidazolinedione nucleus, a 2-thio-2,4imidazoline dione nucleus, and a S-imidazolinone nucleus, andZ represents the non-metallic atoms necessaryto complete a heterocyclic nucleus selected from the class consisting of a thiazole nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, a benzoxazole nucleus, anapththoxazole nucleus, a benzoselenazole nucleus, a naphthoselenazole nucleus, a Z-quinoline nucleus, and a 4-.quinoline nucleus` (References on following page) UNITED STATES PATENTS Brooker 96-105 Kendall et a1 Z510- 240.1 Hensley 96-105 Gerzon et a1 260--240 Brooker et al 2661-240 Brooker et a1. 260-240-1 XR Brooker et a1 2604-240 XR Belgium. France.

22 OTHER REFERENCES Chemical Abstracts, 16, 3101.

Chemical Abstracts, 19, 530.

Coenen et al.: Zeitschrift fur Elektochemie, vol. 57, pages 785 to 795 (1953).

Peters et a1.: J. yof Pharmacology and Exptl. Therapy, V01. 95, pages 226-233 (1949).

Venkataraman: The Chemistry of Synthetic Dyes, v01. 2, pages 1177 to 1183 and 1185 to 1186, Academic Press The., NX'. (1952).

Welch et al.: Science, Vol. 105, pages 486 to 488 (1947).

WALTER A. MODANCE, Primary Examiner.

15 LAS S. RZZO, Examiners. 

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF THOSE REPRESENTED BY THE FOLLOWING FORMULA: 